Danger & Training - Accidents

Posted Monday, February 6, 1995

By Bryan Burke

This is the text of a letter I sent to USPA's safety guy, Jack Gregory, in march of 1994. I have added one or two sentences to clarify some points to the readers on the net. Since writing this I have seen a couple similar incidents and they support my conclusions. Listen people - if you can afford an AAD you can afford a dytter and an altimeter. Use them! Most two canopy situations are caused by lousy altitude awareness.

The following is a summary of some incidents here. People seem to be rather uninformed on this subject, so maybe a few of these will help illustrate some important concepts.

In the course of the last two years I have been noting incidents where a near simultaneous main and reserve deployment left a skydiver with two inflated canopies. For the most part these real life situations back up the industry's tentative conclusion that the best thing to do in this situation is stay with both parachutes unless they are totally separated. (Downplaned with no entanglement at the risers.) However, out of the seven incidents I have detailed information on, none involved totally separated canopies.

Two incidents involved student CYPRES firings during radical canopy maneuvers. In one case, a very experienced jumper had borrowed the rig. As the reserve deployed he cut away the main. Note that the cutaway occured prior to reserve inflation. The other case involved a big, heavy student with about twenty jumps. He was spiralling his main when the reserve deployed. His Raven III (254 sq. ft.) biplaned neatly with his Manta. (288) In spite of several turns, flying in brakes, and other maneuvers the canopies remained in a biplane and the student landed softly.

In these two cases, my recommendations are: convince the manufacturer to recalibrate student CYPRES' for a slightly faster trigger speed, perhaps around 50 mph. (This is now under serious consideration at CYPRES, if they haven't already done it) The experienced jumper should have known better than to be playing around under a canopy with a student AAD. The student attempted to steer his canopy to a particular landing area rather than limit input to that necessary to avoid obstacles. I feel this demonstrates the stability of a biplane well; he did "S" turns and used brakes to set up his approach, and flared the main, all without causing the biplane to break. However, smaller, faster canopies might not have been as forgiving.

Two other biplanes were landed safely after the jumper's AADs fired due to low pulls. Both followed the recommended procedure: leave the reserve brakes on and steer carefully with the main to a clear area. In both cases the main was larger than the reserve.

The other three cases involved AAD firings also. In one, the AAD (type unknown) misfired after the jumper had been under canopy for about one minute. The reserve pilot chute came out at about 1,000 feet but did not begin to extract the canopy until around 500 feet. As the reserve
inflated, it began to fly forward towards the main. When the reserve reached full inflation and docked on the main, the skydiver cut away. The main risers entangled with the right corner of the reserve canopy's lines, resulting in a spin. The jumper landed under the spinning reserve and was injured, although not critically. (Hip dislocation - this could have been far more serious at a dz with more hazards)

In a second case, a low pull caused the CYPRES to fire immediately after the jumper cleared his main brakes. He cut away from the biplane successfully, but I want to emphasize that I feel this to be a very dangerous maneuver. In either a biplane or side by side, the released main
goes up and back as the reserve surges forward and towards the center in the case of a side by side. The potential for a wrap seems very high. (I have about 350 CRW jumps and consider both biplanes and side by sides to be safe and stable configurations. Someone without CRW experience might be less comfortable in these circumstances. A dozen or so CRW jumps with a good instructor might be a great investment in safety knowledge, but don't do it with just anyone and any canopy.)

The final case involves a small Stilleto (about 120 if I remember correctly) and an old five cell Swift (about 175) The two wrapped very quickly, and the jumper spun in under two partially inflated canopies. He was fortunate to land in a recently plowed field, and although painfully bruised was not seriously injured - just sore enough to keep him from jumping for a few days. Several eye witnesses and the jumper agree that if he had landed on a hard surface, his injuries would have been severe if not fatal.

From these incidents I conclude the following:

Loss of altitude awareness can kill you in more ways than one! Five out of seven of these incidents began with this common denominator.

Many people with AADs lack understanding of how they work and their limitations. The FXC shouldn't be used by experienced jumpers, although they are fine for students. FXCs have a strong propensity to misfire high and although you may plan to pull by 2,500, you can't be sure you will. With an FXC set for 1,000 you still have a good chance of it firing if you are pulling at 2,000.

A biplane is safe to land but I don't think cutting away is safe. I feel the same about a side by side - just land it. The exception is...

Jumping a high performance main that is smaller than your reserve is a risky choice. I'm not going to suggest that people with this combination should not use an AAD. But they need to know that if they are at or below 1,500 feet they are better off just pulling their reserve. (Besides the risk of two canopies out, you also have to consider that reloading a used CYPRES is a $100 proposition) At the same time, however, I can't really suggest someone develop yet another emergency procedure for a specialized case. All I know is that experienced jumpers are breaking off too low, trying to long to get a hard pull out, etc. With an AAD - or without - watch altitude and don't mess with deployment problems. Just pull the reserve! Although the likelyhood of having two parachutes out is small, it has become a very real possibility because of AADs, as was the case in all of these incidents. Once you are in this situation, if your main is smaller that the reserve you are the subject of an experiment that could result in
injury or death. This is unexplored territory.

A footnote to the above is that I am not suggesting an AAD makes skydiving more dangerous. Sure, these people had two canopies out, but then, the path that led them to this situation is the same one that leads to people bouncing. They really need the back-up.

I wish I had begun taking detailed notes on subjects like this a long time ago. I'm going to start writing a report on every incident I have the details on, whether hook turn landings or reserve rides - whatever. I think it would be a very interesting project to begin collecting case histories of non-fatal incidents to statistically quantify high risk behavior and refine emergency procedures in cases like the two canopy situations. One of the gut feelings I am getting is that if it were not for improvements in emergency medicine (presence of trained personel is more common, helicopters are more common, EMTs are more experienced) a lot of "incidents" would be fatalities. I am thinking that a non-fatal accident summary, like the annual fatality report, would be of great service to the community.

END MARCH 1994 LETTER TO JACK GREGORY

Bryan Burke, Danger and Training Advisor at Skydive Arizona, CYPRES yes.

Source
Newsgroups: rec.skydiving
Subject: Danger & Training - Accidents
Date: 6 Feb 1995 11:31:25 -0500
Reply-To: skyaz@aol.com (SkyAZ)

Danger & Training - Accidents

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